Amounts
shows the quantity of the element requested.
For example, choosing the amounts column
under
Rainfall Maps
will give a rainfall map of how much rainfall
(in millimetres) has fallen for the time period and area chosen.

If you choose deciles,
this gives an element a ranking,
thus demonstrating how it compares with the surrounds.
For example, a decile rainfall map will show whether
the rainfall is above average,
average or below average for the time period
and area you have already chosen.